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CAVERNS AND THEIR CONTENTS. 
BY D. T. ANSTED, F.K.S. 
Chapter I. 
THE CAVERNS. 
O NE of the great charms of a wild ramble by the sea-side, 
where the cliffs and the waves occasionally meet, and 
where the tidal action is powerful enough to produce a marked 
impression on the form of the shore, is, that we are thus 
constantly presented with varied broken outlines whose 
picturesqueness depends on rock, wind, and weather. But 
within these outlines are frequently deeper recesses, more or 
less concealed, more or less difficult of access, more or less 
occupied by animal or vegetable life, or the remains of such 
life, and into their cavernous recesses one is always tempted to 
penetrate, for in them we rarely fail to find grand and simple 
forms : — rocky vaults arched according to some fantastic plan 
of Nature’s own device ; sepulchres yielding occasionally bones 
of very ancient lords of the soil, and collections of living 
animals of low organization, especially interesting because 
capable of being observed under natural conditions. 
Few rocks so situated on a bold coast are without caverns ; 
but there are two large and very easily recognized kinds of 
material in which caverns chiefly occur. These are granite and 
limestone. The best caverns in every respect are in one or 
other of these rocks ; but they vary in their nature, origin, and 
history, to a remarkable extent. 
The first commencement of almost all caverns may generally 
be traced either to mechanical disturbance connected with the 
upheaval of rocks formed at great depth, and subsequently 
brought to their present position, near the surface of the earth, 
or else to that contraction which has of necessity taken place 
when materials deposited in and with water have solidified, 
parting with their water, and contracting into a smaller space, 
as they ceased to be mud and became compact rock. 
Cracks and fissures, either originally open, or closed almost 
as soon as formed by the introduction of mineral substances, 
that decompose on exposure to weather more rapidly than the 
rocks enclosing them, are thus the fertile causes of most of 
those innumerable natural holes and fastnesses of which poets 
NO. II. L 
